Siren-control system



ZZZ,

H s CAMPBELL SIREN CONTROL SYSTEM Filed Dec. 22, 1922 June 5, 1928.

lustratedin Burke Patent 1,490,313. In that patent as well as in the present one the sig fire alarm and messenger call boxes.

Patented June 5, 1928 UNITED STATES 1,672,302 PATENT OFFICE,

HUGH S. CAMPBELL, 0F HAMMOND, INDIANA, ASSIGNOB'TO FEDERAL ELECTRIC COM- PANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

SIREN-CONTROL sYs'rEm.

Application filed December 22, 1922. Serial No. 808,515.

My invention relates to motor controllers especially adapted for signalling systems and consists primarily of improvements in the apparatus for the same general purpose ilnal as described is an audible one produced by means of a siren driven by an electric motor. Means are provided for stopping the .motor promptly so that the siren will emit blasts which are relatively short and sharp in distinction to the usual sounds which die away gradually with a wailing sound. The Burke patent shows two methods of stopping the motor, viz, reversing the motor leads and dynamic braking. Either of these methods can be employed as a. part of my improved system. According to my system and the One illustrated by Burke, the siren motor is controlled by a controller or circuit changer, the illustrated type being of the kind commonly called a fdrum controller in which there is a rotary cylindrical element with contacts of various lengths upon it. According to the system illustrated by Burke this controller is rotated by an electric motor having certain operating and control circuits. One of my objects is to substitute simpler devices for said motor and control circuits. Another object is to devise a controller in which the operating current is kept out of the drum controller and caused to traverse more rugged switches, provided for the purpose.

To give a brief general description of my apparatus as illustrated, the siren motor is provided with a starting and running switch and a reversing switch. These switches are operated electromagnetically through the agencyof, a drum controller. This controller is driven by means of a spring motor having an escapenient of the type usedniln e spring motor is tensioned'or set by the movement of; a plunger operated by a coil whose circuit is opened and closed by a. switch controlled by a street circuit (of which there may be many distributed throughout the territory from which the signals are to be sent in). When my apparatus is to be used for fire protection or similar purposes the street circuits may be controlled manually, but are frequently conalarm box is employed to control the street circuit and this box is tensioned or set manually and then released, after which it automatically performs its function of openmg and closing the field circuitthe proper number of times and at proper intervals.

Referring now to the particular form of apparatus which embodies the principle of the invention:

Figure 1 is a diagrammatic view of the system as a whole.

, Figure 2 is a view of some of the component parts of the spring motor and esca ement. The view, however, is partially d i grammatic in its nature in order to better illustrate the principle of operation.

Figure 3 is adeveloped view of the surface of the drum controller which is illustrated more diagrammatically in Figure 1.

Like numerals denote like parts throughout the several views.

The siren 1 is of the usual type having a. rotary sound producing element or rotor which is driven b 1 means 9f an electric motor (not specifica 1y shown). The motor is assumed to be within the rectangle 2, Figure 1, and has three terminals a, b, c. The motor illustrated inthis particular diagram is of the'alternating current type,and the operating current is supplied through conductors A, B, G. Let it be assumed that the motor will run forward when the motor terminals a, b, c are connected respectively to the supply conductors A, B, C and will be reversed when connectedin the order A, C, B. In other words, the motor will be reversed by changing the phases B, C.

The motor is controlled primarily by two switches indicated in general by F and R. The switch F when closed will cause the motor to run forward. The switch B when closed will reverse the motor. These switches are controlled electromagnetically. Switch F has a winding 6 which controls a core or plunger 8. 'This is connected'by a rod 10 to two switch arms 11, 12. These are adapted to engage stationary contacts 13, 14 respectively. A tension spring. 16 biases the switch arms toward open position. The reversing switch R is similar in construction to switch F. It has a' winding 18 which controls a core or plunger 19 which in turn operates a rod 20 which is connected to two switch arms 21, 22. These arms are adapted to engage the contacts 23 and 24 respectively. The arms are biased toward open sition by-means of a tension spring 26. he motor terminal a is permanently connectedgto the supply conductor A. The

motor terminal .6 is connected by a conv ductor28 to a conductor 30 which joins the pl conductor C. Switch-arm 12 is connecte by a conductor to sup ly conductor B. Switch arm 21 is connecte by a conductor 36 to suppl conductor B and switch arm 22 1s connects gy a conductor 37 to supply conductor C. e parts are so arranged and constructed that when coil 6 is energized it will close the switch F and cause the motor to run forward. When the coil 18 is energized it will close the switch R'and reverse the motor.

Referring now to the controller which controls the energization of the coils 6 18:

Figure 3 shows the developed view of a drum controller which is preferable in actual practice. It has three contacts 40, 41 and 42, which are represented dia rammatically in Figure 1 by conductive 'scs bearing the same numerals. The spacing be tween the ends of the contacts '41 and 42 are indicated in the diagram by circular strips of insulation 44 and 45. The contacts which will be referred to as discs) are astened to a controller shaft 46. Under normal conditions of rest, shown in the diagram, the coils 6 and 18 will both be deenergized and the motor stand still. When the controller shaft makes a'complete rotation it will first cause the coil 6 to be energized, which will cause the motor to run forward and will then cause the coil 18 to be ener ized which will reverse the motor. The isc is en a ed by a contactor 48 which is connected gy a conductor 49 to conductor D which represents one side of an electric circuit which for identification will be called the setting circuit and is usually -energized by direct current. Disc 41 is engaged by a contactor 50 which is connected by a conductor 51 to coil 6. Disc 42 is engaged by a contactor 52 which is connected y a conductor 53 to coil 18'. The coils 6 and 18 are connected by a conductor 54, which is connected by a conductor 55 to a conductor E which represents the opposite side of the setting circuit.

The setting circuit includes a coil 56 which has a movable core or plunger 58 which is connected by a rod 59 to an arm 60 rigidly fastened to a gear 61 which meshes with a pinion 62 for driving a quadrant 63 which is rigidly fastened to the same shaft 64 with it. The angular movement of arm 60 is limited by two stops 66 and 67 and the construction is such that when coil 56 is energized it will pull arm 60 down (Figure 1) into contact with the stop 67 and will cause the quadrant 63 to rotate a quarter turn in an anti-clockwise direction. Gear 61 is fastened to a housing .68 which contains a coiled spring 70. One end of the sprin is anchored to a casing and the other en is anchored to a shaft 72 which is held in fixed position (angularly) by a rod 73 which passes through the shaft and is normally in contact with a stop 74, being held in'this position by the tension of spring 70. This rod is slidable in the shaft and by means of it the de ree of tension of spring may be regulated While it is not essential, I have shown a second coiled spring 76 which is connected to shaft 64 in such manner as to urgeit in a clockwise direction. This supplements the action of spring 7 0. Quadrant 63 has a toothed peripher which engages a pinion 80 which is rigi y fastened to a shaft 81. A ratchet wheel 82 is fastened to this shaft and cooperates with a pawl 83 which is pivotally mounted on the side of a gear 84. Gear 84 is loosely mounted on shaft 81 and the arrangement and construction are such that when the quadrant rotates anticlockwise, due to the energization of coil 56, the ratchet wheel will click, but when the coil is de-energized and the gears 61, 63 and 80 are urged to rotate under the action of the spring 70, 76 the ratchet wheel will act upon the pawl and cause it to rotate the ears 84 in an anti-clockwise direction. ear 84 meshes with the pinion 86, which is rigidly fastened to the shaft 46 of the controller. Thus the controller is spring actuated to rotate in a clockwise direction but will stand still when the device is being set as a result of the energization of coil 56.

The rotation of the controller shaft is regulated by a time limit device or retarding device WhlCh as illustrated is in the form of an escapement. This escapement consists of a pinion 90 rigidly fastened to an escape wheel 91 adapted to oscillate a detent 92 from which hangs a pendulum 93. The parts 60 to 93 are intended to typify a spring motor and escapement, the details of which may be considerably varied but the function of which is to impart a complete single rotation to the controller shaft 46 each time the plunger 58 descends under the action of coil 56. Such spring motors and esca'pements are in themselves well known in connection with fire alarm and massenger call boxes.

I will now describe the apparatus by which the settitng circuit is controlled. This circuit, as above mentioned, contains the coil 56 and is energized through the supplemental supply conductors D and E. Conductor D is connected to a switch arm 96 adapted to cooperate with a stationary contact 97 as shown at the left end of Figure 1. Contact 97 is connected by a conductor 98 to one end of coil 56, the other end of the coil being connected to conductor E. A spring 99 urges arm 96 toward contact 97 but said switch arm is normally held out of engagement by the influence of a core 100 which is located within a coil 101 and when magnet ized draws arm 96 away from contact with arm 97. It will thus be observed that switch arm '96 also forms-the armature of an electromagnet of which the-other two principal members are core 100 and coil 101. .One end of the coil is connected to a battery 102 for other source of current. This battery is connected by a conductor 104 to an arm 106 which is normally in electric contact with a stationary arm 107 but is adapted to be lifted or separated therefrom by a toothed disc 1.08. to the other end of coil 10].. It will be evident that coil 101 is normally on closed circuitand will release the switch arm 96 only when the circuit is open. Consequently the number of impulses or times whlch coil 56 is energized will depend upon the number of teeth on disc 108, and the intervals at which said coil is'energized will depend upon the manner in which the teeth are distributed upon the periphery of said disc.

The disc is rotated and controlled by a spring motor and escapement similar in principle to the one already described. In the illustrated design a pinion 110 is rigidly fastened to disc 108 and'is driven by a gear 111. The latter is urged to rotate under the action ofaspring 114 tensioned by means of a handle 116 after the manner of an ordinary fire alarm or messenger call box. A time limit'or retarding device regulates the rotation of gear 111. In the present case this is shown as an escapement consisting of a gear wheel 120 which meshes with wheel 111 and is fastened to an escape wheel 122. The latter oscillates a detent 124, which is provided with a pendulum 125. The arms 106 and 107 and the mechanism by which they are controlled are shown to be mounted within a housing 126 shown in dot and dash lines at the lower left corner of Figure 1. These parts may be called, for identification, the controlling mechanism for the street circuit. It will be noted that this controlling mechanism is hand set but is otherwise automatic in operating switch 106.

The operation of the mechanism has been explained in connection with the details of construction, and it will be sufiic-ient to say in summarizing that when the operator pulls the handle 116 (by rotating it toward the right, Figurel) he will set the mechanism and cause it to rotate the disc 108 one coinplete revolution. This will open the street circuit once for every tooth on the disc, and this in turn will cause the setting coil 56 to be energized and de-energized once for every time the street circuitis opened.

Arm 107 is connected by conductor 110' Each energization of the setting coil 56 will cause a. complete revolution of the drum controller 40, 41 and 42, and the complete rotation of this controller will first cause the energization of coil 6 to close the starting and running switch F. Coil 6 will be ener ized in the following manner: from the motor will be energized by connecting the motor terminals a. b, 0 to the supply conductors A, B, C in the order named. So long as the disc 41 is in contact with contactor 50 the contactor 52 will be in engagement with the insulating strip 44 and hence switch R will remain open. The rotation of the siren motor will cause a blast to issue from the siren, and this will continue so long as disc 41 engages'contactor 50. As soon as the insulating portion 45 of disc 41 reaches contactor 50 the conductive portion of disc 42 will reach the contactor 52 and cause the latter to be energized. When this occurs the coil 18 of the reversing switch will be energized as follows: from supplemental supply conductor D through conductor 49 and contactor 48 to disc 40; thence through shaft 46 and disc 42 to contactor As soon as thestartmg and running switch F is closed the 52; thence through conductor 53 to oneend of the coil. The circuit through the coil is completed through the conductors 5'4 and 55 to the conductor E on the other side of the supplemental supply line. It will thus be evident that a complete rotation of the controller first causes the siren motor to be supplied with energy in such manner as to rotate the siren forward and produce a sound. Then after a suitable interval of time the motor leads will be reversed and the current supplied to the motor in such manner as to tend to reverse it. This, of course, brings the motor promptly to rest with the result that the blast will not die away gradually, but-will be brought to a prompt termination. It will also be evident that the number of blasts produced by the siren will be equal to the number of teeth on the disc 108. It is true, of course, that the reversal of the motor leads at a time when the siren motor is rotating forward will give rise to considerable electric stresses in the motor, especially if a motor of considerable size is employed, but these stresses are anticipated and in practice the siren motors for my system are specially built for the purpose.

It will also be observed that in my apparatus the operating currents which drive the siren motor are carried by the switches F, R and not by the drum controller. These switches in practice are rugged and by preference are double break switches in accordance with approved practice. Such switches are well known commercially and are commonly known as electromagnetically operated contactors. In my system the only currents carried by the controller are the relatively weak ones used for energizing the control windings 6, 18.

The same principle applies in the case of a direct current motor, the switch F supplying current to cause the motor to rotate forward, and the switch R supplying current in the reverse direction so as to reverse the motor. Instead of reversing the direction of current a dynamic brake may be used, in which case the switch R will sim 1y short-circuit the armature upon itself, tiius producing a rapid deceleration in the manner well understood by electrical engineers and explained in the said Burke patent.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

A signalling system for giving audible code signals, such system having a siren, an electric motor for rotating it, means including a starting switch for causing the motor to rotate forward, means including a reversing switch for reversing it, means including a winding for operating the starting switch, means including a winding for operating the reversing switch, and means including a controller for controlling said windings, said controller having a rotary element,,.a spring motor for IOtating said rotary element, electromagnetic means for setting said sprin motor, said electromagnetic means inclu mg a core and a winding, one of which is connected to the spring motor for settin r it, and means for controlling the circuit 0 said winding.

In witness whereof, I have hereunto subscribed my name.

HUGH S. CAMPBELL. 

